GRE Prep Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized
for You
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Cars A and B are traveling from Town X to Town Y on the same
[#permalink]
17 Oct 2019, 00:59
17 Oct 2019, 00:59
16
Bookmarks
00:00
Question Stats:
52% (02:49) correct
47% (03:10) wrong based on 85 sessions
Hide Show timer Statistics
Cars A and B are traveling from Town X to Town Y on the same route at constant speeds. Car A is initially behind Car B, and Car A’s speed is 1.25 times Car B’s speed. Car A passes Car B at 1:30 pm. At 3:15 pm, Car A reaches Town Y, and at that moment, Car B is still 35 miles away from Town Y. What is the speed of Car A?
(A) 60 mph
(B) 75 mph
(C) 80 mph
(D) 96 mph
(E) 100 mph
(A) 60 mph
(B) 75 mph
(C) 80 mph
(D) 96 mph
(E) 100 mph
Re: Cars A and B are traveling from Town X to Town Y on the same
[#permalink]
17 Oct 2019, 13:23
17 Oct 2019, 13:23
3
At 1:30 A passes B meaning that during that time they started heading together to town Y with their respective speeds.
At 3:15 A reaches Y but B reaches some other point 35 miles away from Y. Let the distance travelled by B from 1:30 to 3:15 or during 1.75 hr be x.
That means A has travelled whatever B has travelled plus 35 miles.
Putting all these together,
Distance travelled by B during this 1.75 hour = x
Distance travelled by A during this 1.75 hour = x + 35
Speed (B) = distance travelled/time taken =x/1.75
Speed (A) = (x+35)/1.75
Now we are given that,
Speed (A) = 1.25*Speed (B),
(x+35)/1.75 =1.25*(x/1.75)
1.25*x - x = 35
x=35/0.25 = 140
Now plug this value into speed(A) above which gives us 100 mph.
At 3:15 A reaches Y but B reaches some other point 35 miles away from Y. Let the distance travelled by B from 1:30 to 3:15 or during 1.75 hr be x.
That means A has travelled whatever B has travelled plus 35 miles.
Putting all these together,
Distance travelled by B during this 1.75 hour = x
Distance travelled by A during this 1.75 hour = x + 35
Speed (B) = distance travelled/time taken =x/1.75
Speed (A) = (x+35)/1.75
Now we are given that,
Speed (A) = 1.25*Speed (B),
(x+35)/1.75 =1.25*(x/1.75)
1.25*x - x = 35
x=35/0.25 = 140
Now plug this value into speed(A) above which gives us 100 mph.
Re: Cars A and B are traveling from Town X to Town Y on the same
[#permalink]
17 Oct 2019, 21:51
17 Oct 2019, 21:51
1
Bookmarks
3152gs wrote:
At 1:30 A passes B meaning that during that time they started heading together to town Y with their respective speeds.
At 3:15 A reaches Y but B reaches some other point 35 miles away from Y. Let the distance travelled by B from 1:30 to 3:15 or during 1.75 hr be x.
That means A has travelled whatever B has travelled plus 35 miles.
Putting all these together,
Distance travelled by B during this 1.75 hour = x
Distance travelled by A during this 1.75 hour = x + 35
Speed (B) = distance travelled/time taken =x/1.75
Speed (A) = (x+35)/1.75
Now we are given that,
Speed (A) = 1.25*Speed (B),
(x+35)/1.75 =1.25*(x/1.75)
1.25*x - x = 35
x=35/0.25 = 140
Now plug this value into speed(A) above which gives us 100 mph.
At 3:15 A reaches Y but B reaches some other point 35 miles away from Y. Let the distance travelled by B from 1:30 to 3:15 or during 1.75 hr be x.
That means A has travelled whatever B has travelled plus 35 miles.
Putting all these together,
Distance travelled by B during this 1.75 hour = x
Distance travelled by A during this 1.75 hour = x + 35
Speed (B) = distance travelled/time taken =x/1.75
Speed (A) = (x+35)/1.75
Now we are given that,
Speed (A) = 1.25*Speed (B),
(x+35)/1.75 =1.25*(x/1.75)
1.25*x - x = 35
x=35/0.25 = 140
Now plug this value into speed(A) above which gives us 100 mph.
actually it will be 1.45 hour not 1.75 hour
